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排序方式: 共有191条查询结果,搜索用时 15 毫秒
181.
Orton GS Friedson AJ Baines KH Martin TZ West RA Caldwell J Hammel HB Bergstralh JT Malcom ME Golisch WF Griep DM Kaminski CD Tokunaga AT Baron R Shure M 《Science (New York, N.Y.)》1991,252(5005):537-542
The spatial organization and time dependence of Jupiter's stratospheric temperatures have been measured by observing thermal emission from the 7.8-micrometer CH(4) band. These temperatures, observed through the greater part of a Jovian year, exhibit the influence of seasonal radiative forcing. Distinct bands of high temperature are located at the poles and mid-latitudes, while the equator alternates between warm and cold with a period of approximately 4 years. Substantial longitudinal variability is often observed within the warm mid-latitude bands, and occasionally elsewhere on the planet. This variability includes small, localized structures, as well as large-scale waves with wavelengths longer than approximately 30,000 kilometers. The amplitudes of the waves vary on a time scale of approximately 1 month; structures on a smaller scale may have lifetimes of only days. Waves observed in 1985, 1987, and 1988 propagated with group velocities less than +/-30 meters per second. 相似文献
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Caldwell OW 《Science (New York, N.Y.)》1911,33(852):639-642
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Lizards (Tiliqua scincoides) regulated their internal body temperature by moving back and forth between 15 degrees and 45 degrees C environments to maintain colonic and brain temperatures between 30 degrees and 37 degrees C. A pair of thermodes were implanted across the preoptic region of the brain stem, and a reentrant tube for a thermocouple was implanted in the brain stem. Heating the brain stem to 41 degrees C activated the exit response from the hot environment at a colonic temperature 1 degrees to 2 degrees C lower than normal, whereas cooling the brain stem to 25 degrees C delayed the exit from the hot environment until the colonic temperature was 1 degrees to 2 degrees C higher than normal. The behavioral thermoregulatory responses of this ectotherm appear to be activated by a combination of hypothalamic and other body temperatures. 相似文献
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Caldwell OW 《Science (New York, N.Y.)》1939,89(2322):591-595
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Doyle LR Carter JA Fabrycky DC Slawson RW Howell SB Winn JN Orosz JA Prša A Welsh WF Quinn SN Latham D Torres G Buchhave LA Marcy GW Fortney JJ Shporer A Ford EB Lissauer JJ Ragozzine D Rucker M Batalha N Jenkins JM Borucki WJ Koch D Middour CK Hall JR McCauliff S Fanelli MN Quintana EV Holman MJ Caldwell DA Still M Stefanik RP Brown WR Esquerdo GA Tang S Furesz G Geary JC Berlind P Calkins ML Short DR Steffen JH Sasselov D Dunham EW Cochran WD Boss A Haas MR Buzasi D Fischer D 《Science (New York, N.Y.)》2011,333(6049):1602-1606
We report the detection of a planet whose orbit surrounds a pair of low-mass stars. Data from the Kepler spacecraft reveal transits of the planet across both stars, in addition to the mutual eclipses of the stars, giving precise constraints on the absolute dimensions of all three bodies. The planet is comparable to Saturn in mass and size and is on a nearly circular 229-day orbit around its two parent stars. The eclipsing stars are 20 and 69% as massive as the Sun and have an eccentric 41-day orbit. The motions of all three bodies are confined to within 0.5° of a single plane, suggesting that the planet formed within a circumbinary disk. 相似文献
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